Thanks a bunch for this demo. Very straightforward, clear, and quite useful! (BTW, I was raised on Long Island, NY, although I'm living elsewhere now.)
Hi Ian, thanks for putting this video together ; very interesting content and well presented. I bought a 294 mc pro , a 2inch l extreme and an upgraded asi air plus ( used asi air from the original launch ) last weekend. I've just set a dark library for all my usual light frame exposures. I also had a play with flat frame settings and was really concerned with the very strange looking flat frames. They look identical to the ones from your l enhance so I feel more reassured they will calibrate fine. Really good video Ian
Perfect timing for me on this. I have a 294MC, 72mm, and just picked up a used ASI Air Pro. One of my main concerns was taking flats as I've always had some problems with that. Curious though, I've seen much longer exposure times recommended on the 294MC for flats (2-3 seconds (?) in some instances). Will be curious how my processing works as I'll be going straight to PI or Siril. Definitely prefer the Auto exposure version either way
Hi Ian, Very interesting video, I like the auto better, I like the nice rich colors. I am going to put this one in my video folder to watch again. We have had some very ordinary weather over here in Vic' Aust' to say the least. But then again I have been working on my other hobby to get some money for the Asi Zwo294MC pro. Cheers Robert
Robert, many thanks glad you found it helpful, just done a new video on using the ‘plan’ mode of the ASIAIR PRO. Hope your weather improves, I really like the 294MC, Kr Ian
Thank you for doing this video to show the comparison as i was unsure of which to use when i get my 294mc pro. I like the auto one best witht he darker background but thats my eye, both images are great :)
Really interesting comparison, thank you for taking the time to put it together!! :-) 👍👍 P. S, you weren't kidding about the weather at the start of the video!! It's been so cloudy 😂
Thanks Luke, it’s a whole minefield on calibration frames and they can have a big impact on the final image, so I wanted to see what the Auto Flat does and I was pretty impressed, Kr Ian
Greetings from Texas, Ian. Cheers to you for this excellent video as I have been asking the exact question raised, and it seems you have answered the question perfectly. Query: I do not see the exposure calculation for the automated flats, which would be necessary for the creation of dark flat frames. Going from memory, that detail may be in the automated flat file’s metadata or possibly in the file name. Also, I am curious as to why you elect to stack the images using DSS instead of WBPP in PI. By the way, completely off topic, I have been to Bookham many many times in the late 1990s and early 2000s as I was representing PMI in a large patent litigation matter pending in the United States and also represented the company in a few intellectual property transactions. Anyway, love your channel, will be following you from the Great State of Texas. Clear skies, y’all!
Hi Gary, many thanks for subscribing, I only use DSS as it is so quick and simple for OSC images. I’ve never tried PixInsight for stacking, but will give it a go shortly to see what difference it makes. Kr Ian
Ian, when you’re collecting flats for different filters in a filter wheel using auto run, I’m guessing you need to use the auto function rather than manual. Otherwise, you would have to re-calculate the exposure after each filter change. Am I correct?
Hi Joseph, thanks for watching. Yes I do flats with auto run. I make a note of the exposure once they complete and make sure it is the same when I come to do the dark flats for each filter. I think if you press return on the exposure box it retains that for the next chosen image type, I.e. when you move from flats to dark flats (although you have to use bias in the asi air as it doesn’t have a dark flat category). Clear skies, Ian
I see you are using an ASI294MC Pro. I'm considering this camera but I've read the flats exposure should be 3 to 5 seconds to alleviate calibration artifacts etc. You obviously aren't having any issues from what I can see. Have you ever had calibration artifacts using ASIAir auto flats. I have an C8 SCT. I'm testing a light panel now with an embroidery ring with T shirt material. Even at the lowest panel brightness two sheets of T shirt is too bright. Test with four T shirts, still won't calibrate. I used the white sleeve to store the light panel. With this it finally calibrates. The histogram is average 47303. Exposure is auto calculated at 10secs. My goal is 5 second exposure with the histogram below 32768. When I use manual method 5 seconds, four T shirts, white sleeve. panel on lowest dimmable setting then I get 23671 average a little too low. Panel dimming isn't adjustive in fine enough amounts. I'm thinking of purchasing some neutral density filter film to tape on the panel.
Hi, thanks for watching. No I’ve never had any calibration artefacts using the ASI auto flat. I use a white rugby shirt doubled over the lens, a light panel and the ASI auto flats are usually around a third of a second. I do dark flats at the same frame rate and all seems to work fine. I have high histograms similar to yours, when I did manual I aimed for 25,000 to 30,000, but the high histogram doesn’t seem to impact in the calibrated image. Clear skies Ian
Hi Dennis, no Dark Flats are done at the same exposure as your Flats, not the Lights. Flats will usually be a very short exposure as you are putting a lot of light into the sensor, even using the T shirt method, which I do. So here I think it was 0.06 for Auto Flats and then I did Dark Flats at 0.06 to match the Auto Flat exposure length and I did Dark Flats at 0.0345 to match the manual Flats I did at that exposure length. So although there were two sets of Dark Flats each were done to match the appropriate Flat images, but not the long exposure of the Lights. Kind regards Ian
![Lp. Сердце Вселенной #60 РОЖДЕНИЕ ЛОЛОЛОШКИ [Финал] • Майнкрафт](http://i.ytimg.com/vi/YoR0pAV9FVQ/mqdefault.jpg)
Thanks a bunch for this demo. Very straightforward, clear, and quite useful! (BTW, I was raised on Long Island, NY, although I'm living elsewhere now.)
Hi Ian, thanks for putting this video together ; very interesting content and well presented. I bought a 294 mc pro , a 2inch l extreme and an upgraded asi air plus ( used asi air from the original launch ) last weekend. I've just set a dark library for all my usual light frame exposures. I also had a play with flat frame settings and was really concerned with the very strange looking flat frames. They look identical to the ones from your l enhance so I feel more reassured they will calibrate fine. Really good video Ian
Thanks Paul, glad it was helpful. Good luck with the 294, it’s a great camera. Kind regards Ian
Perfect timing for me on this. I have a 294MC, 72mm, and just picked up a used ASI Air Pro. One of my main concerns was taking flats as I've always had some problems with that. Curious though, I've seen much longer exposure times recommended on the 294MC for flats (2-3 seconds (?) in some instances). Will be curious how my processing works as I'll be going straight to PI or Siril. Definitely prefer the Auto exposure version either way
Interesting finding thanks for sharing it with us
Achim, many thanks glad you enjoyed, kind regards Ian
Astounding difference
!!
thanks for sharing
Hi Ian, Very interesting video, I like the auto better, I like the nice rich colors. I am going to put this one in my video folder to watch again. We have had some very ordinary weather over here in Vic' Aust' to say the least. But then again I have been working on my other hobby to get some money for the Asi Zwo294MC pro. Cheers Robert
Robert, many thanks glad you found it helpful, just done a new video on using the ‘plan’ mode of the ASIAIR PRO. Hope your weather improves, I really like the 294MC, Kr Ian
Thank you for doing this video to show the comparison as i was unsure of which to use when i get my 294mc pro. I like the auto one best witht he darker background but thats my eye, both images are great :)
Really interesting comparison, thank you for taking the time to put it together!! :-) 👍👍
P. S, you weren't kidding about the weather at the start of the video!! It's been so cloudy 😂
Thanks Luke, it’s a whole minefield on calibration frames and they can have a big impact on the final image, so I wanted to see what the Auto Flat does and I was pretty impressed, Kr Ian
Very informative, thanks I have learned a lot!
Specifically, what should one use as a light source for flats?
Greetings from Texas, Ian. Cheers to you for this excellent video as I have been asking the exact question raised, and it seems you have answered the question perfectly. Query: I do not see the exposure calculation for the automated flats, which would be necessary for the creation of dark flat frames. Going from memory, that detail may be in the automated flat file’s metadata or possibly in the file name. Also, I am curious as to why you elect to stack the images using DSS instead of WBPP in PI. By the way, completely off topic, I have been to Bookham many many times in the late 1990s and early 2000s as I was representing PMI in a large patent litigation matter pending in the United States and also represented the company in a few intellectual property transactions. Anyway, love your channel, will be following you from the Great State of Texas. Clear skies, y’all!
Nice demonstration, I've just subscribed for more..... Can I ask, why stack in dss and not pix? I have a 294mc pro as well...
Hi Gary, many thanks for subscribing, I only use DSS as it is so quick and simple for OSC images. I’ve never tried PixInsight for stacking, but will give it a go shortly to see what difference it makes. Kr Ian
Thanks for this. Although It looks to me like you flipped the shots at the end.
Ian, when you’re collecting flats for different filters in a filter wheel using auto run, I’m guessing you need to use the auto function rather than manual. Otherwise, you would have to re-calculate the exposure after each filter change. Am I correct?
Hi Joseph, thanks for watching. Yes I do flats with auto run. I make a note of the exposure once they complete and make sure it is the same when I come to do the dark flats for each filter. I think if you press return on the exposure box it retains that for the next chosen image type, I.e. when you move from flats to dark flats (although you have to use bias in the asi air as it doesn’t have a dark flat category). Clear skies, Ian
I see you are using an ASI294MC Pro. I'm considering this camera but I've read the flats exposure should be 3 to 5 seconds to alleviate calibration artifacts etc. You obviously aren't having any issues from what I can see. Have you ever had calibration artifacts using ASIAir auto flats. I have an C8 SCT. I'm testing a light panel now with an embroidery ring with T shirt material. Even at the lowest panel brightness two sheets of T shirt is too bright. Test with four T shirts, still won't calibrate. I used the white sleeve to store the light panel. With this it finally calibrates. The histogram is average 47303. Exposure is auto calculated at 10secs. My goal is 5 second exposure with the histogram below 32768. When I use manual method 5 seconds, four T shirts, white sleeve. panel on lowest dimmable setting then I get 23671 average a little too low. Panel dimming isn't adjustive in fine enough amounts. I'm thinking of purchasing some neutral density filter film to tape on the panel.
Hi, thanks for watching. No I’ve never had any calibration artefacts using the ASI auto flat. I use a white rugby shirt doubled over the lens, a light panel and the ASI auto flats are usually around a third of a second. I do dark flats at the same frame rate and all seems to work fine. I have high histograms similar to yours, when I did manual I aimed for 25,000 to 30,000, but the high histogram doesn’t seem to impact in the calibrated image. Clear skies Ian
Don't you shoot Dark-Flats at the same exposure time as your Lights??
Hi Dennis, no Dark Flats are done at the same exposure as your Flats, not the Lights. Flats will usually be a very short exposure as you are putting a lot of light into the sensor, even using the T shirt method, which I do. So here I think it was 0.06 for Auto Flats and then I did Dark Flats at 0.06 to match the Auto Flat exposure length and I did Dark Flats at 0.0345 to match the manual Flats I did at that exposure length. So although there were two sets of Dark Flats each were done to match the appropriate Flat images, but not the long exposure of the Lights. Kind regards Ian